1. Field of the Invention
The present invention relates to a method for isolation and/or purification of human growth hormone by a hydrophobic interaction chromatography.
2. Description of the Prior Art
Purification procedures of human growth hormone are disclosed in many publications, for example:
(1) Biochimica et Biophysica Acta, 74, 525(1963), PA1 (2) Federation Proceedings, 16, 775(1957), PA1 (3) Endocrinology, 77, 1126(1965), PA1 (4) Recent Progress in Hormone Research, 15, 71(1959), and PA1 (5) Acta Endocrinologica, 66, 478(1971). PA1 (1) extracting frozen pituitary glands with a neutral or weakly basic buffer, PA1 (2) subjecting the extract to precipitation with a precipitant, PA1 (3) extracting the resulting precipitate with a neutral or weakly acidic buffer, and PA1 (4) purifying the extract by column chromatography (e.g. gel filtration using Sephadex.RTM.G etc., ion-exchange chromatography using DEAE-cellulose etc.).
For the purpose of clinical use, the purification of human growth hormone should be carried out under mild conditions so that the denaturation of human growth hormone is minimized. In addition, since human pituitary glands are so limited in amount, an efficient procedure for isolation of human growth hormone must be employed from the view point of saving the limited natural resources.
A typical process for extracting and purifying human growth hormone which has heretofore been employed comprises:
However, the other pituitary hormones cannot be removed satisfactorily and, in addition, some salts contaminate the human growth hormone by these known processes.